First Engine Build - Advice Needed

Throw the ridge reamer away and never use it again. If you need to use it, the bores are shot anyway, and all you did was make it harder to get the bores correctly.

Find a machine shop. If you want to do the assembly yourself you are making a mistake. You need to have all the tools to measure everything. Plastigauge don't cut it.

Back to the bores...it's very difficult to find 10 HP in the bores or even the short block but it's damn easy to lose 40-50 HP with crap bores.