Some advice
A 360 engine will probably have Speed Pro Hypers because of the price, not entirely what the compression would be with mid 70's 360 heads.
There basically the same as the KB-107's except with a coated skirt for longevity and *I think* a slightly shorter height. With a .039 thick head gasket on a zero deck height & a 72cc head, it will have a 9.8-1 ratio. A .055 will drop it to (IIRC) 9.5-1.
Do not mill the deck if you don't need to. Have all the block work done and install the rotating assembely first. Check the deck height of the slugs first. After you measure how far down in the hole first, add this to the compression ratio mathematics to figure out the ratio. As stated above, a slight alteration of the ratio can be made with the head gasket.
Try the 60401 cam over the 60402 with the (tall tires) Hwy. gears, stock converter combo.
(It will just simply work better with the fire size you have now.)
If all else fails, and "That sound @ idle" MUST be had, install the Hughes Whiplash or That other small whatcha-ma-call it ruff idle Mutha Thumper cam and be done with it. Don't look back. Just forget about it.
With the Hwy. gears, stock converter and the possible taller tire later, any cam not designed for the street, towing with a duration of greater than 218 @ .050 will just disappoint. Pay attention to the cam manufactures cam descriptions! Do not ignore them!
Read them! Use your head.
Or I'll be saying, "I told you so!"
Have a good one, I'm out.