Got a vise and hacksaw and utility knife and screwdriver?

Remove the lines with a box end wrench 6pt preferred or a 6pt socket preferred, whatever fits best. A COUNTERHOLD (the female hole for the banjo bolt is in a bigis almost a must on the cooler ends because of the torque required fat nut shaped thing to counterhold) to pop it loose against the copper crush washer grip (some antiseize on the new installed crush washers will be a future blessing and show class).

Pad the vice jaws and clampt the flats of the banjo ends in the vice and prop the hose somehow. Using the hacksaw, cut at an angle across the metal hose crimp towards the banjo end, where the crimp is compressed to the tightest radius, cutting as deep as possible without nicking the banjo metal tube (you'll be cutting thru the rubber hose at the same time). Make your angle as parallel to the hose axis as possible and still have the hacksaw blade frame clear all.A WHIZ WHEEL WORKS WONDERS HERE.

Continue the cut away from the start point, spiraling around the crimp fitting in a stretched spiral around the fitting until the cut is finished except for the last little bit at the start end, and pop that with a screwdriver in the slot. Pry the crimp fitting off, and usint the utility knife, slit the hose along the long axis to the end of the banjo fitting nipple. Peel the hose off the fitting. It may be glued/adhered to the nipple, so scrape it as clean/smooth as possible. You can burn it clean with a torch if you keep the temp away from max and just scorch off the rubber.

The nipple should have square cornered sealing rings, like 3 of 'em. As long as you have the nipples clean, you can get a new seal on new hose with a hose clamp.

I didn't bother, but you can buy woven hose armor to replace the old (or even reuse the old and hide any new leaks), I didn't bother, but just used slit lengths of the old hose to get the new past rubs and the radiator core support. I bought oil proof hose sized to the nipples in a length equal to the old ones, looking for at least pressure to 100psi, plus 4 of the good stainless screwdrive hose clamps, 8 of 'em if you are at any degree paranoid, measure new hose off old hose, cut, route, and install.

I would lay some 200grit sandpaper on a flat surface (glass is nice) and rub the flat mating surfaces on the banjo fittings to be sure there's no spurs or nicks or gouges to hinder seal. File/sand off spurs and use some plastic metal to slightly overfill nicks/gouges and sand flat, starting with 80grit until flat.

NOTE:
Banjo bolts are somewhat fragile, being hollow and having a sizable hole so follow the torque limits - should seal on the new copper washers with minimal pressure. Banjo bolts use 2 copper crush washers each, so you need 9 new ones (the oil drain plug uses the same washer and the washers are one time use)... Use one under the bolt head and one between banjo head and cooler/adapter seal surface around the hole. You can buy these at any auto parts if you take an old one to measure off of, along with the banjo fitting to match to the hose... A smear of silicone lube on the nipple will make installing tight hose a breeze.

Most of the v6's have at least a seep leak as the old rubber hose rots invisibly inside the liner...