Kooky,
The 292 specs I have (I measured my 292 cam and it agrees) are those of the Clevite 229-1551
Lobe 232 232 valve 406 406 lift
Dur 188-188 at .050
LSA 111.5
1.5 degrees retard so
LCI=113.0
LCE=110.0
Then again the cam I measured was in a 30-over engine so it is possible the bone stock cam is different and I measured a Clevite rebuild.
For your use, given it is a fresh new long block, I'd leave the cam alone and just do intake and exhaust.
Lots of wet carb icing weather in Seattle, agreed you need the exhaust heat. Only other option would be use the Langdon exhaust, and if you have room in the truck, run a 1" spacer from an old Ford Galaxie, the heater hoses run thru it so that heats the base of the carb. You might get away with that but I like your idea too of keeping the stock heat base.