Help with Engine cleaning?

Hi all,

I have a very dirty '72 360 LA block and wanted to know a few things.

What is the best way to clean the block inside and out?

My dad has a high pressure hose and high pressure air hose on his farm and I don't want to pay a shop to do what I can. It will go to check everything is straight eventually.

Also should I clean the rust in the water jackets? If so, how?

I will be doing some oiling mods, can I use a normal steel drill bit at the right dimensions?

Thanks,

B