Penta 4.3 & Penta Drive

I have a 1994 4.3 Penta. the Block overheated and needs replacement. I have been told its a reverse drive, but all tecs I speak with say in a single engine a reverse drive would not be installed. How can I tell the rotation of the engine and if the drive is regular or reverse. I have been told I can use a gm block 1992 to 1994 from Chevy van or truck, and just add the marine parts that the engines are the same. Before I begin spending serious money I would appreciate some guidance or suggestions on how you think I should proceed. On the block the 3rd bracket from from holding the cam shift shows serious sign of heat discoloration.

Ayuh,.... What diagnostics have ya done, to know ya need a new motor,..??

Compression test,..??

Standard Chevy motors are left-handed when viewed from the workin' end,....
Clockwise when lookin' at the pulleys,...

In simpler terms. Your engine is standard rotation. They do not make a counter rotating 4.3. (Not saying you cannot make one)

If you purchase a automotive engine it will not work in your boat. Get a reman 4.3 marine engine and do it right or don't bother.