Moon Patrol rom not displaying properly?

[Matt68061]

Hi all...have something that seemingly should be pretty simple to figure out but I am at a loss.  Retropie is still a bit foreign to me so I hope someone knows an easy fix.

I have a horizontal set up and my Moon Patrol rom displays with horizontal bars on each side.  Like it is being cropped for a vertical monitor.  I have added and deleted the rom. Obviously I have gone into the video settings in the tab menu and nothing seems to get it to display full screen?

Using Advmame .94 with a clean (run thru clrmamepro) rom.  Displays fine running on a pc but not on my Pi3.

Any thoughts on this? All my other horizontal games appear correct? Wondering if there is some config file that gets saved somewhere that I am missing?  Attached a few pics for reference. Metal Slug appears fine....if you can tell.

Thanks in advance for any advice.

[Matt68061]

By the way, I cant seem to resize the pics any smaller...if someone can educate me on that....fantastic 

[akafox]

Any image editing program should have a resize option. What OS do you use?

If you don't have any image editing software worth anything and are tring to save money to build an arcade machine then you can use GiMP it's free and works easily.

You open the picture click the resize option (Shift+T)  resize it and the fit the canvas to image (image ---> fit canvas to layers)
If you are taking th pics with your phone and posting...there should be a simple program on your phone that will do resizing.

[KTURNER]

Would you be happy playing the nes version.