Can I replace my 4L60-E transmission with a 4L80-E transmission

Yes.
You will need to have ur computer flashed for the 4L80E (flash for a 3/4 or 1-ton truck). You will also need the wiring harness for the 80.

Another option is to flash the truck for a manual tranny, then run the tranny as a stand-alone unit. Controllers can be found online for the tranny. This would be the way to go if u were running a carb/non-computer motor.

Running the 80 over the 60 is not necessairly the better choice. You will need a conversion u-joint to mate ur factory driveshaft (that u had to shorten) to the output of the tranny. Crossmember will need to be altered (or replaced with one from a 1-ton). If the truck is 4wd u also have the t-case to deal with.

It may be better to build/rebuild the 60 with performance parts, depending on ur application.

Not recommended,to many conversions,fix it back stock 4L60-E.

l see your ..sounds right to me! l might check into beefing up my 4L60 trans myself..now!!