If you installed a boot manager and don't need one, it can be removed. The boot manager would appear as:
F1 FreeBSD F5 Drive 1 Default: F1
That's boot0 (aka booteasy). What you want is an MBR that just chains to the first active partition. Install it with "fdisk -B da0", or whatever your devicename is. If you want boot0 back, run "boot0cfg -B da0".