Keith, If you're using a 48 block, you can probably get away with getting some new ferrules and using your current fittings.
In any case, you can use flexible copper tubing, and that's what you'll get if you order the kit. Only difference on the kit, it comes with the sweat fitting already in place.
In the case of my 39 block, I about had to use the "sweat" fitting because I didn't have clearance to make the bend up the side cover and clear the cover itself if I used a comp. fitting and ferrule.
My previous motor (a 46) was a different story. It had regular fittings and comp. ferrules. On the 46 side cover, there was also an outward indention in the side cover that allowed more room for the tubing coming out of the block and bend upwards. It wasn't there on the side cover on the 39 motor.
Unfortunately, as I stated earlier... The lines don't come out in the same place on the different blocks, so I wasn't able to use the 46 side cover.
If you're going to buy tubing, I would suggest that you get between 2.5 - 3 feet of it. You should have plenty extra, but it will give you alot more to play with, and what the heck, it's cheap.
This helped in my case, as on the bend to the oil distributor, I had to bend it differently than the stock bend, as it wouldn't clear my exhaust. I guess that's what happens when you start mixing parts. Good Luck.
