Looks just like a 3rd gen assembly

. It's a royal PITA. It might be easier, if you don't want to drill holes, to remove the whole assembly. It's not hard, but once you have the assembly out you can't just remove the motor and replace. You have to hold it with a c-clamp or vice to keep the counter balance spring from cutting off your arm. This is why doing it in the car might be easier, totally up to you but they both take about the same amount of time only once is more tedious where the other takes more tools.
I'd quote 2-3 hours but that it could take 4.
__________________
, Jon
Owner of a Red Sled.
If it\'s EFI I can tune it. Specialize in 82-95 GM (yes Lt1\'s)
\"If you can leave black marks on a straight from the time you exit a corner till the time you brake for the next turn.......Then, you have enough horsepower\" - Mark Donohue