Conservator and guardian question; Can I petition to be conservator?

Guardianship pertains to care, housing and welfare of the person. Conservator controls the funds. It seems odd that brother was removed as conservator but left on as guardian.

You stated there is no money and your not sure you want to be conservator. It’s a cumbersome and costly process. Sounds to me like you should leave well enough alone.

I agree with DollyMe. Go for guardianship. Find a certified Elder Care Lawyer for assistance. Find and read the laws of your state on guardianship of the elderly. Check with your tax preparer on exactly how to keep records and maybe even locate a CPA for info.
I did it for Luz for two years before she passed away.
The only thing I did outside of the court was to submit a n IRS for that allowed me to sign for her on our tax returns. this was very simple and only has to be submitted once to activate and once to terminate. worked great.
In Nevada, any account with a balance over $10,000 must be blocked to protect the protected persons money. Court permission was required for large expenses.
I was granted permission to spend up to $250.00 a month for her more common neds. Like the La Maze bras to help prevent the fungal infection under the breasts. ( Luz loved them. And I quit worrying about the infection recurring.) Or the disposable underwear.
Being the spouse I declined other forms of expense reimbursements just took care of my wife like I had done for years and the Judge acknowledged that.
Usually the lawyers fee is paid for from the protected persons funds.
As the guardian you control the money and, here at least, all of her medical care.
Which can be split if needed with another person. I did it all and it worked great for us.
Best of luck and good wishes to you.

Yes you can and under these circumstances I would. I would also go for guardianship, get your brother out of the picture entirely. Court appointees only do what by law they have to do, that is it. That would always be my last choice.