My 1966 Ford 289 installed is about 1.65". I talked to PAC springs for a recommendation, standard dual springs, not beehive. Summit hooked me up with 1.9", 1.55" valves with retainers and keepers for the Chev valves. Now need the money for the machine shop to install bronze guides and do the valve job going from 1.78" intake to 1.9" intake. Ordered the springs through Summit as PAC does not sell to private citizens.
The difference between 1.625" and 1.8" is very obvious with a tape measure, enough to know the beehive are not an option.
Then valve length is to be considered. Chevy are about 4.9", a bit shorter than my Ford valves. Worst case to get geometry correct will be lash caps.
Something to think about. I know the purists will be having a hemmorage over Chevy parts ruining a Mopar, but sometimes you have to look at what works for an inexpensive upgrade.