Hi,
Please cover your intake and exhaust when the engine is naked ! Dust, sand and moisture have a free ride inside your engine. To lazy to read back, but did you install the oil seal with some oil or grease ? When I install a seal, I cover the shaft with thin plastic sheet (thin bag or the plastic foil you use for food) and slide the seal over the plastic with lot's of grease / oil. This particular seal is difficult to install, I install it at the same time when I install the crank, as one piece (maybe you did that, maybe not). Installing this seal afterwards should be done careful, with a nice flat piece of steel (with an hole in the middle for the shaft itself) and push it straight in, over the plastic covered shaft. Make sure you only press the outer part of the seal, otherwise you will ruin the seal, it is a large seal with a small hole, therefore weak when it comes to installation.
Make sure the surface of the shaft is perfect in the sealing area, use sandpaper 2000 to smooth the surface and make it hold oil together with the seal (protect the bearing for the dust). Remember, seal and surface make the combination, a good seal will leak on a bad surface, a good surface will leak with a bad seal ! Both have to be in perfect shape !
However, since this seal is clamped between the crankcases, I prefer to split the cases installing it, when the engine is out of the frame anyway.
About the paint, well, I always bring my stuff away for painting to a professional, if he/she says the paint is resistant, it's his / her financial responsibility when it's not, including my hours to disassemble and assemble.
But, heads up, it's only a seal, and it's only paint.
You will finish the bike in 2014 for sure, these are only minor setbacks ! and happens to most of us once in a while.
If I was a boy, I'd throw tools - that would probably make me feel better!
Look at my signature, and understand the importance of it ! A great peace of mind in this case is to find rest in your head, let the anger / frustration go, and start over again when
you are ready. Throwing things, hammer it, etc, will take you further away from your goal !
that engine is NOT that complex, it's fairly straight forward
The CB72/77 engines are complex !, not because the amount of parts but because all parts are crucial and have to be good. Not often I see a good working CB72/77 engine without oil leeks, noisy top ends, wrongly installed kick starter mechanism etc, etc. Believe me when I say that any Honda four engine are easier engines to work on !
Within a few hours it will be 2014, I wish you a very happy new year !
Jensen