66 c10 motor mount position

[Chevy nutcase]

Yanked out my great running 250 and 4 speed to make room for a 350 backed by a tremec tkx and I was wondering the pros and cons of using the current engine perch location vs moving it forward using an available hole? I know using the current location is advisable if I were going to reuse the sm420 bell crossmember but that too is getting removed. I've read on here the forward location will offer some welcome firewall clearance