The new Street Demon is similar in architecture to the ThermoQuad and has only been out a couple of years. If you have had your carb for 10 years or so, it won't be one of the new style Street Demons.

IFRs are usually just a drilled orifice, just like the PVCRs. So you either drill and tap them and buy a handful of bleeds. Or you can get some thin wires and if necessary, some small drill bits. Same results either way.

I have a street/strip 499 that pulls to about 6,000. I went from an 850 to a 950 and then to the 1050 Dominator that is on there now. But the Dominator is a chore to tune for the street. If the carb is tuned properly, you will be hard pressed to over-carb a hot 500" Mopar.