depends on what your goal is.

drop the restorer. BB supports are basically Repairers+engineers+ scout. The number of each type of support will depend on your personal preference

5 eng 2 rep at a minimum.

Plus extra gunners for AA and one more support... eng or repair. - or drop the AA gunners and have two more supports

Personally, I liked the efollowing setup when leveling US:

2 BO - minimum +14 POT Allows you to keep your supports even or ahead of your BO. Nothing worse than a 34kt Monty becasue your Engies aren't past 90 yet.

4 Gunners - 2 12/11 or 11/11 for the mains (ACC-RLD-ACC classing) and 2 10/12 or 11/12 or 11/11 for T slots(RLD-RLD-RLD and DON'T class as AA gunners). I used to run a ton of AA but with the subs these days I find myself running HH alot more

5-6 Engies - +12 preferred but +11 will work. Very importand to keep all of your engies at the same level. 1 low lvl engie will have a horrible effect on the others, reducing speed and, more importantly, OH. I prefer 6 Engies as US is a speed nation, you can't AW their BB's so, the more OH the better

3-4 Reps - Same as above +12 or +11 Reps are important but Engies more so. I personally run 3.

1 Scout - +12 Aircraft - Don't be the noob who complains he can't see anything when he doesn't even carry a scout himself.

This setup will give you more than enough sailors for a BB6, allow you time to bring them all up together (the 2 BO's), and give you some flexibility in playstyle. If you get in a fleet that does HA's, you may not want the secondary gunners as your fleetmates will provide AA and ASW, but for GB they may be invaluable. it's always nice to have options and the setup above will do that for you.

P.S. If you're going to spend money on Elites, do Engies first. Gunners cap easily and you'll be pulling rookies off of your BO at higher levels to control your lines.

hope this helps

My current setup lets me play with flexibility.

It is possible (or at least used to be) to hit the repair cap with x4 elite repairs

I also prefer to have 6 engys, but not elites. +11 is fine enough with a +12 repair stat, which helps overall hitting that important repair cap. the combined ability of all 6 engies results in a VERY long overheat time.

2 more elite repairs classed into acc and reload gunners. at the time they hit lvl 120 they will have reached the acc and reload caps, even tho leveling will be tough, you are focusing on the end game anyhow and wanna get the best bang for your buck.....quite literally.

If you forgo everything else at least have a scout, that way you arent totally screwed by the time you hit nebby.

If you want to get to 900 SD as fast as possible, you can use a setup I call "Support Gunners". This only works for US, and is relies on the fact that basic support sailors can use pretty much everything under 6" in size. It works like this...

Take two elite reload sailors (or reload 12 at minimum) and make them into SUPPORT SAILORS at level 12. Then never promote them again. They will continue to provide excellent repair and restore skill while being able to operate AA guns (5/38 mk38L or 3/70 mk23N), hedgehogs, mines, and basic torpedoes. The trade off is a lackluster reload skill. You use them on your T slots to give you weapon options as well as high SD ability.

At the point you have 900 SD WITHOUT using these two sailors, you work on replacing them by leveling up proper reload gunners for AA and HH work (or repairers if you want nothing in your T slots, such a waste!). This is about the time you have to level up another engineer or two for use in Montana and Nebraska anyway, so you're not losing any time here.