My wife says I'm a hoarder. She just didn't use the word hoarder.
I don't bring home "junk" any more unless I have plans for it within two weeks. Her love and hugs for me helped me to tone it down. Based on what you said. I'd also tell him you were scared of him when he was cussing you and you are too much of a lady for him to use the "f-bomb" around you. (Providing your language isn't filled with "f-bombs" on occasion. Then that arguement sounds false and hypocritical.)
I would ask your husband to hold a garage sale for five or six items he says he is going to fix up and sell. Ask him what items he would like to put in the garage sale and how long it will take him to fix those things. Then ask him to put an ad in the newspaper or where ever garage sales are advertised in your area. Hand him the form to fill out for the garage sale and tell him you love the way he is looking out for your well being by fixing things and making a profit. Tell him you'll submit the garage sale ad for him since he'll be busy fixing things up to put in the garage sale.
Then love him. Ask him how things are going with the fixing. If he goes out to the back yard or garage or where ever and works on something, go out and tell him how proud you are of his ability to fix things. Use positive reinforement. Be proactive. When he fixes the first thing, tell him you think that's wonderful, etc. Tell him you think he's wonderful, etc.
Those things should help you clear some of your yard and garage. After you have the first garage sale, work on the second. If he gets frustrated with the fixing because something can't be fixed, tell him if he can't fix it no one could fix that, but you are glad he tried. Ask him if he can't fix it could he take it to a scrap metal dealer so he can sell it. Then he can use the money to buy the parts necessary to fix the next thing.
If its hot and sweaty work, when he's fixing something, bring him something cool to drink. (The drink should be non-alcoholic since he will be working around tools, some of which may be power tools.)
You get the idea. Are some of these things bothersome and difficult? Not to my point of view. Just remember you are cleaning your garage and yard, which was your origonal goal. (If you want some other motival ideas e-mail me. I'll tell you what my wife did for me.)
If you have been a real NAG, apologize to him. Tell him you would like to start fresh and ask his forgiveness. If he is amazed and doubtful of your sincerity, that tells you you have been a shrew and nag, from his perspective. When I taught the Marriage and Family class to the men in my church, one of the things I told them was to bring their wives flowers and tell their wives how much they appreciate them. I'd say that if your wives ask or think "What have you been up to?". Its been too long since you've brought your wives flowers and expressed your gratitude to them for them. Then I told them if they needed to they could tell their wives I told their husbands to do that (bring flowers). The same applies to you.
Good luck to you and yours.