When you have as nice a wood grain painting technique as you do, why bother with decals? Your paint will age much better than any decal, and each models is unique. (no repeated pattern! )
Ha! There's really no bad choices there, it's a nice body style that can wear many colors well! I think that silver would be mighty fetching on it, but that's my taste. I notice your reference pics favor a black vinyl top...
Looking forward to more progress on this one.
Sounds like you are doing everything right, so don't sweat it. Keep using common sense, quit scaring yourself, and you'll get through. Remember Churchill's words about fear...
Hang in there, and build a model!
So they did! I had in my head ( a bad place to store anything) that the removable side cover was an indicator of the smaller Hydra. Backasswards again!
The B&M Hydro used the GM case, so appears pretty well stock from the exterior; the B&M magic was internal, so this should be a viable option for your purpose.