I had to have the drop down bracket re custom made to make mine work, it didn't drop them enough to clear the PS ram, cost me $20 to have it made, still have the original around somewhere.
We just installed some 6901's on my sons 72 small block. Not near the clearance headache as the old 70's BlackJacks (purchased used) that we had on the car, till now. But we experience numerous issues with the 6901 that turned into a significant larger ordeal than it should have been. Here's the problems we encountered with hooker 6901 1) steering box clearance, very very very minor ding for clearance. It wasnt hitting but it was about .030" away. Now its got about .190 or so. this was essentially a non issue and quick. 2) top idler arm bolt thread projection had to be trimmed. I could have simply turned bolt around, but then it couldnt be removed when the headers were installed. I just trimmed it back .25 or so; this was the better solution for us. Other owners may choose to reverse the bolt. Non issue quick easy. 3) The forward (right, viewed from the fender) header bolt for cyl 4 could not be installed, when mated to the head. It required quite a bit of effort on the bench with spare head to massage pipe for bolt installation clearance. 4) spark plug socket wouldnt fit on cyl 1 and cyl 8, the flange interfered. This will not be an issue with small 14mm plugs. We are using old heads (351W-D0OE) with the large 18mm plugs. We used a die grinder to make nice trim for the socket clearance. Note, we have seen this on several header brands lately. The large spark plugs are just sort of overlooked, in the fitment. I have no idea why. Maybe they were always like that, but, I have installed and reinstalled many many sets of small block block ford headers since '79 and I do not ever recall having to trim a flange to simply be able to use a plug socket. 5) during final bolt-up we saw that cyl 6 rear-most bolt would not fit either, and cyl 5 rearmost bolt was pretty iffy. We had to file the weld away on cyl 5 by hand (no clearance to use grinder and small disk), plus massage the tube a somewhat. 6) pitman arm is contacting the header tube on left hand turns, after about 1 1/2 turns. parking lots and tight manuevering may be an issue, may not. This is common and most just deal with it. Our old headers hit too, but not quite soon. One HUGE Recommendation, buy some header bolts that have the super reduced head (3/8" wrench flats). This is going to be an immense help for bolt up and tightening in place. Headers on mavericks are and have always been a chore! I honestly think product accurateness has dropped off since the 70's/80's. I know the flange and spark plug clearance issue is something we never dealt width, or I just dont remember. Tube clearances are always an issue (normally) and some small massaging is required generally. this is expected, but the flange bolt access and spark plug socket not clearing are problems. overall somewhat content with 6901's. plus we have 1 5/8 tubes too (were 1 1/2)
It helps when a set of headers are specifically designed for the car. Hooker 6901's are not. They just happen to bolt up to some Mavericks/Comets.
