The generator matrix

 1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  7  1  1  1  1  1  1  1  1  1  7  1  1  1  1  1  1  1  1  1  1
 0  7  0  0  0  0  0  0  7  7 35 14  7 28 14 21 14 28 28 42 35 28 14 21 35 28  0 35 14 35 35 14 14 28  0  7 21 28 28  7 21 14 42  7  7  0  0 35  0 35  7 35  7 42  7  7 28 35  7  0 28 42 28 42  0 35 28  7 42
 0  0  7  0  0  7  7 28 35 28 14 42 14  7 35  7 28  0 21 28  0 14 42  7  0 35 42 14 21 21  7 35 28 28  0 42  0  7  0  0 42 42  0 28 14 42 42 35  7 28 35 42 42  0 14 28 21 42 28  7 42 42 42 14 28 42 28 28  0
 0  0  0  7  0 35 28 21 35  0 42 14 35  7  0 35  0 21 28  7 14 21 21 21 35 35 28 42  7 21 35 35  0  0 28 21 21 14 42  0 35  7 28 28  0 14 42  0 42 35 21 28 14 28 35 14 42 28 21 21 42 35 42 14  7 21 35 35 21
 0  0  0  0  7 35  7 14 35 28 14 42 42  0 14  0 42 35  7 42 21  7 28 14 14 28  7  7  7 21 28 14 14 42 35 35  0 21 14 28 14 28 35 35 42 35  0 21 42 28  0 28  7 28 28 35  0 35  7  7 42  7 14 28 28 35 35 21  0

generates a code of length 69 over Z49 who´s minimum homogenous weight is 378.

Homogenous weight enumerator: w(x)=1x^0+642x^378+1290x^385+1608x^392+1836x^399+2058x^402+1902x^406+24696x^409+1902x^413+74088x^416+2004x^420+1866x^427+1470x^434+1020x^441+732x^448+444x^455+54x^462+24x^469+12x^476

The gray image is a code over GF(7) with n=483, k=6 and d=378.
This code was found by Heurico 1.16 in 35.7 seconds.