Need tips on installing DSE tubs in 67 camaro

[KSBRKTRACER]

I've done a search in the forums on installing the tubs and really didnt come up with much, found quite a few pictures of some nice installations but no real advice. I have all of the needed equipment and the skill level needed to do the work. Just looking to see if anybody had run into any problems or knew of any shortcuts. Also I have not bought the tubs yet but I am getting ready to order them, any vendors that have a deal on them ???? Do they come with any patterns for cutting and trimming the car ??? If I use the offset rear hangars (I have a set of speed-tech) how much room do I gain ??
I have 295/65/15 e-t street radials on a 15x10 4.5 bs billet specialty wheel that sets pretty much even with the outside of the 1/4 panel. My goal is to change backspace and pull the wheels in far enough to lower the ride heighth. I'm not gonna to narrow the rearend any further as I have brand new 35 spline strange axles in it. ANy advice would be greatly appreciated.