Newbie tyre advice

[dfps]

Hi,

Some advice please.

I have Caravelle 16 "alloys fitted to my California with 215 x 65 x16c tyres fitted.
I think my alloys are called Mitoya...... not the prettiest of alloys but they will be fine for me as I not planning on entering any
shows and prefer the understated look.

By mistake I have bought a set of 4 virtually brand new 205 x 65 x 16c that came of a new T5.1.

I saw them advertised as transporter tyres on steels and as it was a wet and dark night when I picked them up didn't think to check
them for size.

2 months later , I have now gone to get them fitted and only just realised they are not the same size as the tyres currently on the alloys
on the Cali.

Two of my tyres on the Cali are really good but 2 need changing.

QUESTIONS: 1.

1. Will the new 205 's be ok to use on the alloys ? Will they fit with no problems ?

2. If they will fit with no problems, will I need to change all 4 ? as there will be 205's on the back and 215's on the front.

3. Are there any benefits of one size over the other ?

4. Should I stick with the 215 size and just buy 2 new tyres of the original size and try to sell the complete 205 set as they are standard T5.1
factory issue ( Hankooks ) with less than 20 miles on them.?

Any advice greatfully received.