I can certainly appreciate why some would replace with LED's but I think I would like to just keep it stock and restore rather than modify anything.
Yeah...I feel the same way. While LEDs are more trouble free...I too prefer to keep mine stock, and TBH, every time I see someone who rewired their tape deck or console VU meters for LEDs instead of the incandescent lamps...I never much like the look. Yeah, you can find LEDs that sorta simulate that incandescent glow, but not really. There is always something stark looking about them...especially when some folks opt for the blue-light or that bright-white look.
Also...I'm not sure you want to go with 8V lamps...because I think they will simply glow less bright since there is only 6V feeding them. They will last a long time, so it's not like you'll be changing burned out lamps every couple of weeks. I went with what the specs called for, 6V.
When you do find your final supplier...post back where you got them. So we have a record for the next guy who needs some.
I am currently running Logic Pro X on an iMac with a UAD Apollo 8 Quad interface and the added satellite box. So I have 8 channels. My Otari is a 32 track however, once everything is done, I will most likely end up using the 24 track head that came with it for the added track width. Would this be possible with my current setup and the addition of a sync box of some sort?
Yeah, with your 8-channel setup, you will want a way to sync to the DAW for sure, since you can only transfer 8 tracks at a time from tape to DAW. I've got full 32 channel converter capability...but I still like using a synchronizer with the deck. It lets me have a solid time reference on both deck and DAW, and when moving things back-n-forth, everything is locked.
I actually run a master clock & "house sync" generator box, that feeds my Timeline sync box with a video sync and also my DAW converters with Word clock. The Timeline then feeds the tape deck and has full transport control of it via proper cable, and it's also tied to the DAW, which is the Master for timeline control and it sends MIDI MTC to the Timeline.
It's a bit involved, and if you get to that stage and want more specific details of my setup, I can provide them...but it's a full, bidirectional sync solution, though I always run it with DAW as the Master, and the deck chase/locks to it (well to the whole sync rig)...that way the DAW never has to chase if it was the other way around, which can cause more issues than the when the tape deck is Slave and chases.
Sometimes it feels a bit sloppy because the tape deck is a mechanical device and needs time to wind up/down...while a DAW is instant...but once you get the gist of it, and know how to properly stripe the tape, and pre-roll when working...then it's just a matter of giving the deck the time it needs to spin up and lock, which is usually 3-5 seconds when things are right.
Anyway...start small...get the deck in proper shape. Don't waste your time recording until you've overhauled it and done as full an alignment and calibration as you can...and then after that you'll be good to go for a long time. The MX-80 decks are workhorses, and they don't "drift" out of spec too easily, unless the machine is pretty worn to begin with.
Clean all your contact points...I mean, everything inside and out that you feel comfortable doing. I pulled every PCB every connector on my deck and de-oxidized & treated each connection point. Yeah...it will take you a few days of work to do all that, plus any repairs or like the VU lamp replacements...but well worth it.
Oh...and yeah, the XLR Pin 3 hot thing you can either change oh the actual machine, or do it on the cable snake at either end. In my case, since the channel snake went to a patchbay, when I soldered the patchbay ends I ran the Pin 3 wire to the Tip connection in the patchbay..which was much easier then flipping them internally in the deck.