Palmbob?

Palmbob, if you check in this weekend, maybe you would help me with any kind of suggestion.....
I just took in cat #7..(2 of them dumped on our property, neighbor took the other)...he went in for neutering about 5 weeks ago. I've been trying to get him socialized with the other two cats who would be his roomies, but it's not going well and I can't trust him to leave him alone with them. DH is allergic to cats and we have two motorhomes, so 3 cats live in one, 2 cats in the other and one cat (who has FIV) lives in the house. He can't stay outside with the coyote situation so he's in the workshop at night and outside with me while I'm working outside all day in the nursery. He's sweet, loving, lap-sitting...and has attacked me viciously 4 times now. Even when 'at rest' his tail is mostly twitching and he seems somewhat agitated. A couple of hours ago I was on my knees weeding and he was beside me...I kinda got the vibe a second or two before he attacked my leg. He's quite a hunter/ killer and I get the feeling that if he hasn't found something to take his aggresssions out on, he'll go after me if I'm there. The vicious bite on my hand a couple of weeks ago became infected, so it's getting harder to cut him any slack and I've warned the DH and DS not to trust him. I'm afraid I'm going to have to go in and talk to our vet Monday a.m. and see about having him put to sleep. I've never encountered a cat like this before...what do you think? I appreciate any input you might have. Thank you.
Sherry