RE: S-25 rebuild
Yeah, why not check with your lhs or HPI? What's the worse they're going to tell you...no??
Second, you'ld probably have been better off to have just replaced the engine as to buy the parts. The cost for a new engine is not that much more than all the parts and you'ld have a more powerful engine and a warranty.
Now, to your questions.
To get the old bearings out, heat the block to about 425 degrees f. The bearings should come out fairly easily. Just be careful, it's hot. To put the new ones in, freeze them for 30 min or so. If you need to tap them in to seat them use a socket with the same diameter as the outer race but smaller than the seat it's going into.
If the sleeve is a tight fit you need to verify that the block is not out of shape. They can be tight but usually not so thight that the sleeve won't go in. You can also freeze the sleeve to get it to shrink a bit. When you freeze parts to get them to go in you need to be sure to oil them once they're installed to prevent any condensaton from forming rust.