1965 C's are a different bird.A lot of one year only schtuff.
First year for slip yoke,last year for cable shifted trans.
Gas tank is a one year only thing,too.So is all the trim.
Motor mounts are one year only on the 65 C's.
Schumacher makes conversion kits for them so you can install a 66-up B/RB engines but for the V8 subs only--none for the slant six.
The front sub frame is different compared to other Mopars,the torsion bar anchors are part of the sub frame (others have anchors as part of the body/floor)
The sub frame is very beefy and still bolts to the unibody.It too is 65 only and was slightly revised in 66 along with the floorpans and trans tunnel.
Disc brakes were not available until 1966.
There are aftermarket kits available,and the popular 1973 C body parts upgrade (spindles,caliper brackets,calipers,rotors,lower ball joints) works great.
Slant six Fury's came with poverty 11X2" rear drums and 11X2-3/4 fronts.
As mentioned,you may have to mess around with the trans cable shift and steering column.
The 65/66 Fury's do share some common sheetmetal and mechanical parts but be prepared to find things do not match.Rear quarter panels are different.
The 65/66 Fury's have the shortest wheelbase --and are the lightest of all 65-78 C body cars and are a good platform to build any kind of machine Pro-touring,drag car,or a really nice street machine.
I strongly recommend doing your homework on the C's before diving onto the project before hitting any major unknown snags.
Here are a few sites that are C body specific..
http://www.cbodydrydock.com/news.phphttp://www.moparfins.com/forum/default.asphttp://www.forcbodiesonly.com/http://cbodyhomeport.yuku.com/Hope this helps.