I'm going to check tomorrow on a set of 3kGT twin turbo heads, if swapped how you've explained, the heads externally look like they'll work, but im going to have to check out the cam situation.

I'll post info as i find out, unless you've actually done this or have a set of DOHC heads.

V45W - 1999, 3.5 sohc, winter package
L042G- 1987, 2.6 carb, auto - Cylon Raider
A112 - 1973 Galant Wagon - 4G63 Turbo, 5 speed
L023G - 1983, 2.6 carb, 5 speed manual 4WD
L028 - 1983, 4D55 turbo diesel 2WD