nice car. i just did exactly what you are wanting to do for my '70 bee clone. bought a running 400ci from a buddy a few years back, then found a stroker kit for sale in the race parts for sale section here on moparts.com last summer. after hurting my 440 last winter i decided that i was going to take the plunge and build the 500ci lowdeck. i paid $400 for the 400 engine, $1600 us dollars for the kit (never used 440source 0.040" over 4.125" stroke) plus shipping which was a couple hundred more. i had the machining done at competition automotive in richmond hill for another $1750, that included cam bearings, install main studs and align hone, bore, hone, zero deck block, balancing, pin hone pistons, performance valve job and adjust installed spring heights and cc one chamber on the heads, and a set of head and intake gaskets. then i bought a mopar m1 intake that was just over $300 shipped. i did the assembly and re-used alot from the 440 like oil pan, timing chain and cover, dampner, rockers, valve covers, carb etc. so depending what you have you're looking at like $4000 to $5000. are you anywhere near toronto? i think i've seen your car at moparfest maybe? anyway, pm me if you want any help or info finding stuff or whatever, i love black '70 bees