My son swears by Doug Thorley headers. Very thick flange and great fit. I believe these are the TRI-Y design. They come in ceramic and chrome and are very expensive. They don’t indicate any restriction regarding torsion bars.

http://dougthorleyheaders.com/produ...MC/model/TRUCK/sfID1/9/sfID2/35/sfID3/33

Don’t know if this is the article you’re looking for, but here’s how I did the hydraulic clutch on my 1960 GMC:

http://sixty7ss.proboards.com/index.cgi?board=engine&action=display&thread=666

And another link showing a more recent improvement and even better looking design:

http://67-72chevytrucks.com/vboard/showthread.php?t=365466

1960 GMC 1/2-Ton Pickup Truck
In the Gallery
Updates in the DITY Gallery
Now cruising in the Passing Lane