Lot's of working going from a OBDI to OBDII engine. If you want an L67. I'm sure you could find an 3.8 supercharged OBDI from a bonneville. That would make wiring and a computer easier to do.

That only has 205 hp, but you could probably mod that engine easier than a DOHC. There aren't a lot of DOHC mods out there you can buy and bolt on.