The plot thickens. 1964 C20

[Desert dog]

Thanks to the advice of those here, we got the '86 305 engine mated to the bell housing and tranny. It all went smoothly until the engine mount bolts reared their ugly heads. After some not so gentle persuasion we won the day. But then the plot thickened.
In looking around we have discovered a couple of opportunities for further learning.
1. The truck has what's left of the driveline hand brake. Only the drum is left in place. Is this something that can be found, or is there a way to convert to rear axle emergency brakes?
2. The 305 has a hole just above the oil filter. I believe it is for the oil pressure sending unit. The original copper line from the dash to the top of the intake is still in place. Is there a way to connect the original line to the engine at this location?
I would appreciate any help or advice you can offer.

Regards from the frying pan that is Tucson,
Desert dog