Is this a good buy?

[SPD319]

Unless I'm missing something here, I'm thinking this is a pretty good find. A friend of mine has offered to sell me the following:
Superlift 4" lift kit including bilstein shocks
Edge platinum w juice tuner
Motorcraft tranny filter
Motorcraft blue spring kit

$450

The kit is new, but is missing the rear blocks and its 5 years old NIB
The tuner is used and missing the egr thermo
Other items are new

I don't know much about Superlift, but I looked up that a set of rear leaves would run me about $500 and a egr thermo would be under $50. I'm doing the deal. Hope it wasn't a mistake. I was going for a 6" lift with 37's .... What size tires would I be able to squeeze under a 4"?

[dhanna6powerstroke]

Buy it then resell the Edge and use that money towards an SCT with custom tuning and a monitor.

[shawnb99]

a 35 would be best bet depending on BS of wheel, the egr probe is no biggie, i would buy it new anyway. as far as the lift, superlift has been somewhat reputable, but still usually stiff as all get out. the bilsteins ( 5100 i asume) is a great shock, but it is also a little firmer, the two together will be a daily reminder that you are in a lifted heavy duty truck.