I have a 4Gb hard-drive with a 1Gb Windows NT partition at the beginning of it. I wanted to install RedHat 6.1 with a 16Mb boot partition all the way at the end of the disk and then a 1Gb root partition immediately preceding it. I wanted to organize the disk in this way so that if I decided to grow either the NT or Linux partition later, there would be room to do so. Neither the graphical nor the text installer would let me do this. Both of them reordered the partitions I specified to suit their preferences. Even when I attempted to create a "filler" partition to move the / ad /boot partitions to the end of the disk, the installer reordered the partitions to put the / partition before the filler partition. The partition tool in the installer should allow the user to specify exactly where on the disk the partitions should go. If this doesn't seem like a feature that will be of interest to most users, then it should be hidden in an "advanced mode" or something, but it should be there.
The feature that you are looking for is called fdisk and it is available by performing an expert-mode installation (just type "expert" at the boot prompt) Keep in mind that most (read that 99%) of Intel machine will not boot from beyond 1024 cylinders on a drive, therefore your plan to put /boot at the end of a 4G drive will not work at all. You are probably going to end up having to put the 16M /boot partition at the beginning of the drive and then doing whatever you want with the root and swap partitions.